SEO
How To Build A Diverse & Healthy Link Profile
Search is evolving at an incredible pace and new features, formats, and even new search engines are popping up within the space.
Google’s algorithm still prioritizes backlinks when ranking websites. If you want your website to be visible in search results, you must account for backlinks and your backlink profile.
A healthy backlink profile requires a diverse backlink profile.
In this guide, we’ll examine how to build and maintain a diverse backlink profile that powers your website’s search performance.
What Does A Healthy Backlink Profile Look Like?
As Google states in its guidelines, it primarily crawls pages through links from other pages linked to your pages, acquired through promotion and naturally over time.
In practice, a healthy backlink profile can be divided into three main areas: the distribution of link types, the mix of anchor text, and the ratio of followed to nofollowed links.
Let’s look at these areas and how they should look within a healthy backlink profile.
Distribution Of Link Types
One aspect of your backlink profile that needs to be diversified is link types.
It looks unnatural to Google to have predominantly one kind of link in your profile, and it also indicates that you’re not diversifying your content strategy enough.
Some of the various link types you should see in your backlink profile include:
- Anchor text links.
- Image links.
- Redirect links.
- Canonical links.
Here is an example of the breakdown of link types at my company, Whatfix (via Semrush):
Most links should be anchor text links and image links, as these are the most common ways to link on the web, but you should see some of the other types of links as they are picked up naturally over time.
Mix Of Anchor Text
Next, ensure your backlink profile has an appropriate anchor text variance.
Again, if you overoptimize for a specific type of anchor text, it will appear suspicious to search engines like Google and could have negative repercussions.
Here are the various types of anchor text you might find in your backlink profile:
- Branded anchor text – Anchor text that is your brand name or includes your brand name.
- Empty – Links that have no anchor text.
- Naked URLs – Anchor text that is a URL (e.g., www.website.com).
- Exact match keyword-rich anchor text – Anchor text that exactly matches the keyword the linked page targets (e.g., blue shoes).
- Partial match keyword-rich anchor text – Anchor text that partially or closely matches the keyword the linked page targets (e.g., “comfortable blue footwear options”).
- Generic anchor text – Anchor text such as “this website” or “here.”
To maintain a healthy backlink profile, aim for a mix of anchor text within a similar range to this:
- Branded anchor text – 35-40%.
- Partial match keyword-rich anchor text – 15-20%.
- Generic anchor text -10-15%.
- Exact match keyword-rich anchor text – 5-10%.
- Naked URLs – 5-10%.
- Empty – 3-5%.
This distribution of anchor text represents a natural mix of differing anchor texts. It is common for the majority of anchors to be branded or partially branded because most sites that link to your site will default to your brand name when linking. It also makes sense that the following most common anchors would be partial-match keywords or generic anchor text because these are natural choices within the context of a web page.
Exact-match anchor text is rare because it only happens when you are the best resource for a specific term, and the site owner knows your page exists.
Ratio Of Followed Vs. Nofollowed Backlinks
Lastly, you should monitor the ratio of followed vs. nofollowed links pointing to your website.
If you need a refresher on what nofollowed backlinks are or why someone might apply the nofollow tag to a link pointing to your site, check out Google’s guide on how to qualify outbound links to Google.
Nofollow attributes should only be applied to paid links or links pointing to a site the linking site doesn’t trust.
While it is not uncommon or suspicious to have some nofollow links (people misunderstand the purpose of the nofollow attribute all the time), a healthy backlink profile will have far more followed links.
You should aim for a ratio of 80%:20% or 70%:30% in favor of followed links. For example, here is what the followed vs. nofollowed ratio looks like for my company’s backlink profile (according to Ahrefs):
You may see links with other rel attributes, such as UGC or Sponsored.
The “UGC” attribute tags links from user-generated content, while the “Sponsored” attribute tags links from sponsored or paid sources. These attributes are slightly different than the nofollow tag, but they essentially work the same way, letting Google know these links aren’t trusted or endorsed by the linking site. You can simply group these links in with nofollowed links when calculating your ratio.
Importance Of Diversifying Your Backlink Profile
So why is it important to diversify your backlink profile anyway? Well, there are three main reasons you should consider:
- Avoiding overoptimization.
- Diversifying traffic sources.
- And finding new audiences.
Let’s dive into each of these.
Avoiding Overoptimization
First and foremost, diversifying your backlink profile is the best way to protect yourself from overoptimization and the damaging penalties that can come with it.
As SEO pros, our job is to optimize websites to improve performance, but overoptimizing in any facet of our strategy – backlinks, keywords, structure, etc. – can result in penalties that limit visibility within search results.
In the previous section, we covered the elements of a healthy backlink profile. If you stray too far from that model, your site might look suspicious to search engines like Google and you could be handed a manual or algorithmic penalty, suppressing your rankings in search.
Considering how regularly Google updates its search algorithm these days (and how little information surrounds those updates), you could see your performance tank and have no idea why.
This is why it’s so important to keep a watchful eye on your backlink profile and how it’s shaping up.
Diversifying Traffic Sources
Another reason to cultivate a diverse backlink profile is to ensure you’re diversifying your traffic sources.
Google penalties come swiftly and can often be a surprise. If you have all your eggs in that basket when it comes to traffic, your site will suffer badly and might need help to recover.
However, diversifying your traffic sources (search, social, email, etc.) will mitigate risk – similar to a stock portfolio – as you’ll have other traffic sources to provide a steady flow of visitors if another source suddenly dips.
Part of building a diverse backlink profile is acquiring a diverse set of backlinks and backlink types, and this strategy will also help you find differing and varied sources of traffic.
Finding New Audiences
Finally, building a diverse backlink profile is essential, as doing so will also help you discover new audiences.
If you acquire links from the same handful of websites and platforms, you will need help expanding your audience and building awareness for your website.
While it’s important to acquire links from sites that cater to your existing audience, you should also explore ways to build links that can tap into new audiences. The best way to do this is by casting a wide net with various link acquisition tactics and strategies.
A diverse backlink profile indicates a varied approach to SEO and marketing that will help bring new visitors and awareness to your site.
Building A Diverse Backlink Profile
So that you know what a healthy backlink profile looks like and why it’s important to diversify, how do you build diversity into your site’s backlink profile?
This comes down to your link acquisition strategy and the types of backlinks you actively pursue. To guide your strategy, let’s break link building into three main categories:
- Foundational links.
- Content promotion.
- Community involvement.
Here’s how to approach each area.
Foundational Links
Foundational links represent those links that your website simply should have. These are opportunities where a backlink would exist if all sites were known to all site owners.
Some examples of foundational links include:
- Mentions – Websites that mention your brand in some way (brand name, product, employees, proprietary data, etc.) on their website but don’t link.
- Partners – Websites that belong to real-world partners or companies you connect with offline and should also connect (link) with online.
- Associations or groups – Websites for offline associations or groups you belong to where your site should be listed with a link.
- Sponsorships – Any events or organizations your company sponsors might have websites that could (and should) link to your site.
- Sites that link to competitors – If a website is linking to a competitor, there is a strong chance it would make sense for them to link to your site as well.
These link opportunities should set the foundation for your link acquisition efforts.
As the baseline for your link building strategy, you should start by exhausting these opportunities first to ensure you’re not missing highly relevant links to bolster your backlink profile.
Content Promotion
Next, consider content promotion as a strategy for building a healthy, diverse backlink profile.
Content promotion is much more proactive than the foundational link acquisition mentioned above. You must manifest the opportunity by creating link-worthy content rather than simply capitalizing on an existing opportunity.
Some examples of content promotion for links are:
- Digital PR – Digital PR campaigns have numerous benefits and goals beyond link acquisition, but backlinks should be a primary KPI.
- Original research – Similar to digital PR, original research should focus on providing valuable data to your audience. Still, you should also make sure any citations or references to your research are correctly linked.
- Guest content – Whether regular columns or one-off contributions, providing guest content to websites is still a viable link acquisition strategy – when done right. The best way to gauge your guest content strategy is to ask yourself if you would still write the content for a site without guaranteeing a backlink, knowing you’ll still build authority and get your message in front of a new audience.
- Original imagery – Along with research and data, if your company creates original imagery that offers unique value, you should promote those images and ask for citation links.
Content promotion is a viable avenue for building a healthy backlink profile as long as the content you’re promoting is worthy of links.
Community Involvement
Community involvement is the final piece of your link acquisition puzzle when building a diverse backlink profile.
After pursuing all foundational opportunities and manually promoting your content, you should ensure your brand is active and represented in all the spaces and communities where your audience engages.
In terms of backlinks, this could mean:
- Wikipedia links – Wikipedia gets over 4 billion monthly visits, so backlinks here can bring significant referral traffic to your site. However, acquiring these links is difficult as these pages are moderated closely, and your site will only be linked if it is legitimately a top resource on the web.
- Forums (Reddit, Quora, etc.) – Another great place to get backlinks that drive referral traffic is forums like Reddit and Quora. Again, these forums are strictly moderated, and earning link placements on these sites requires a page that delivers significant and unique value to a specific audience.
- Social platforms – Social media platforms and groups represent communities where your brand should be active and engaged. While these strategies are likely handled by other teams outside SEO and focus on different metrics, you should still be intentional about converting these interactions into links when or where possible.
- Offline events – While it may seem counterintuitive to think of offline events as a potential source for link acquisition, legitimate link opportunities exist here. After all, most businesses, brands, and people you interact with at these events also have websites, and networking can easily translate to online connections in the form of links.
While most of the link opportunities listed above will have the nofollow link attribute due to the nature of the sites associated with them, they are still valuable additions to your backlink profile as these are powerful, trusted domains.
These links help diversify your traffic sources by bringing substantial referral traffic, and that traffic is highly qualified as these communities share your audience.
How To Avoid Developing A Toxic Backlink Profile
Now that you’re familiar with the link building strategies that can help you cultivate a healthy, diverse backlink profile, let’s discuss what you should avoid.
As mentioned before, if you overoptimize one strategy or link, it can seem suspicious to search engines and cause your site to receive a penalty. So, how do you avoid filling your backlink profile with toxic links?
Remember The “Golden Rule” Of Link Building
One simple way to guide your link acquisition strategy and avoid running afoul of search engines like Google is to follow one “golden rule.”
That rule is to ask yourself: If search engines like Google didn’t exist, and the only way people could navigate the web was through backlinks, would you want your site to have a link on the prospective website?
Thinking this way strips away all the tactical, SEO-focused portions of the equation and only leaves the human elements of linking where two sites are linked because it makes sense and makes the web easier to navigate.
Avoid Private Blog Networks (PBNs)
Another good rule is to avoid looping your site into private blog networks (PBNs). Of course, it’s not always obvious or easy to spot a PBN.
However, there are some common traits or red flags you can look for, such as:
- The person offering you a link placement mentions they have a list of domains they can share.
- The prospective linking site has little to no traffic and doesn’t appear to have human engagement (blog comments, social media followers, blog views, etc.).
- The website features thin content and little investment into user experience (UX) and design.
- The website covers generic topics and categories, catering to any and all audiences.
- Pages on the site feature numerous external links but only some internal links.
- The prospective domain’s backlink profile features overoptimization in any of the previously discussed forms (high-density of exact match anchor text, abnormal ratio of nofollowed links, only one or two link types, etc.).
Again, diversification – in both tactics and strategies – is crucial to building a healthy backlink profile, but steering clear of obvious PBNs and remembering the ‘golden rule’ of link building will go a long way toward keeping your profile free from toxicity.
Evaluating Your Backlink Profile
As you work diligently to build and maintain a diverse, healthy backlink profile, you should also carve out time to evaluate it regularly from a more analytical perspective.
There are two main ways to evaluate the merit of your backlinks: leverage tools to analyze backlinks and compare your backlink profile to the greater competitive landscape.
Leverage Tools To Analyze Backlink Profile
There are a variety of third-party tools you can use to analyze your backlink profile.
These tools can provide helpful insights, such as the total number of backlinks and referring domains. You can use these tools to analyze your full profile, broken down by:
- Followed vs. nofollowed.
- Authority metrics (Domain Rating, Domain Authority, Authority Score, etc.).
- Backlink types.
- Location or country.
- Anchor text.
- Top-level domain types.
- And more.
You can also use these tools to track new incoming backlinks, as well as lost backlinks, to help you better understand how your backlink profile is growing.
Some of the best tools for analyzing your backlink profile are:
Many of these tools also have features that estimate how toxic or suspicious your profile might look to search engines, which can help you detect potential issues early.
Compare Your Backlink Profile To The Competitive Landscape
Lastly, you should compare your overall backlink profile to those of your competitors and those competing with your site in the search results.
Again, the previously mentioned tools can help with this analysis – as far as providing you with the raw numbers – but the key areas you should compare are:
- Total number of backlinks.
- Total number of referring domains.
- Breakdown of authority metrics of links (Domain Rating, Domain Authority, Authority Score, etc.).
- Authority metrics of competing domains.
- Link growth over the last two years.
Comparing your backlink profile to others within your competitive landscape will help you assess where your domain currently stands and provide insight into how far you must go if you’re lagging behind competitors.
It’s worth noting that it’s not as simple as whoever has the most backlinks will perform the best in search.
These numbers are typically solid indicators of how search engines gauge the authority of your competitors’ domains, and you’ll likely find a correlation between strong backlink profiles and strong search performance.
Approach Link Building With A User-First Mindset
The search landscape continues to evolve at a breakneck pace and we could see dramatic shifts in how people search within the next five years (or sooner).
However, at this time, search engines like Google still rely on backlinks as part of their ranking algorithms, and you need to cultivate a strong backlink profile to be visible in search.
Furthermore, if you follow the advice in this article as you build out your profile, you’ll acquire backlinks that benefit your site regardless of search algorithms, futureproofing your traffic sources.
Approach link acquisition like you would any other marketing endeavor – with a customer-first mindset – and over time, you’ll naturally build a healthy, diverse backlink profile.
More resources:
Featured Image: Sammby/Shutterstock
SEO
How to Revive an Old Blog Article for SEO
Quick question: What do you typically do with your old blog posts? Most likely, the answer is: Not much.
If that’s the case, you’re not alone. Many of us in SEO and content marketing tend to focus on continuously creating new content, rather than leveraging our existing blog posts.
However, here’s the reality—Google is becoming increasingly sophisticated in evaluating content quality, and we need to adapt accordingly. Just as it’s easier to encourage existing customers to make repeat purchases, updating old content on your website is a more efficient and sustainable strategy in the long run.
Ways to Optimize Older Content
Some of your old content might not be optimized for SEO very well, rank for irrelevant keywords, or drive no traffic at all. If the quality is still decent, however, you should be able to optimize it properly with little effort.
Refresh Content
If your blog post contains a specific year or mentions current events, it may become outdated over time. If the rest of the content is still relevant (like if it’s targeting an evergreen topic), simply updating the date might be all you need to do.
Rewrite Old Blog Posts
When the content quality is low (you might have greatly improved your writing skills since you’ve written the post) but the potential is still there, there’s not much you can do apart from rewriting an old blog post completely.
This is not a waste—you’re saving time on brainstorming since the basic structure is already in place. Now, focus on improving the quality.
Delete Old Blog Posts
You might find a blog post that just seems unusable. Should you delete your old content? It depends. If it’s completely outdated, of low quality, and irrelevant to any valuable keywords for your website, it’s better to remove it.
Once you decide to delete the post, don’t forget to set up a 301 redirect to a related post or page, or to your homepage.
Promote Old Blog Posts
Sometimes all your content needs is a bit of promotion to start ranking and getting traffic again. Share it on your social media, link to it from a new post – do something to get it discoverable again to your audience. This can give it the boost it needs to attract organic links too.
Which Blog Posts Should You Update?
Deciding when to update or rewrite blog posts is a decision that relies on one important thing: a content audit.
Use your Google Analytics to find out which blog posts used to drive tons of traffic, but no longer have the same reach. You can also use Google Search Console to find out which of your blog posts have lost visibility in comparison to previous months. I have a guide on website analysis using Google Analytics and Google Search Console you can follow.
If you use keyword tracking tools like SE Ranking, you can also use the data it provides to come up with a list of blog posts that have dropped in the rankings.
Make data-driven decisions to identify which blog posts would benefit from these updates – i.e., which ones still have the chance to recover their keyword rankings and organic traffic.
With Google’s helpful content update, which emphasizes better user experiences, it’s crucial to ensure your content remains relevant, valuable, and up-to-date.
How To Update Old Blog Posts for SEO
Updating articles can be an involved process. Here are some tips and tactics to help you get it right.
Author’s Note: I have a Comprehensive On-Page SEO Checklist you might also be interested in following while you’re doing your content audit.
Conduct New Keyword Research
Updating your post without any guide won’t get you far. Always do your keyword research to understand how users are searching for your given topic.
Proper research can also show you relevant questions and sections that can be added to the blog post you’re updating or rewriting. Make sure to take a look at the People Also Ask (PAA) section that shows up when you search for your target keyword. Check out other websites like Answer The Public, Reddit, and Quora to see what users are looking for too.
Look for New Ranking Opportunities
When trying to revive an old blog post for SEO, keep an eye out for new SEO opportunities (e.g., AI Overview, featured snippets, and related search terms) that didn’t exist when you first wrote your blog post. Some of these features can be targeted by the new content you will add to your post, if you write with the aim to be eligible for it.
Rewrite Headlines and Meta Tags
If you want to attract new readers, consider updating your headlines and meta tags.
Your headlines and meta tags should fulfill these three things:
- Reflect the rewritten and new content you’ve added to the blog post.
- Be optimized for the new keywords it’s targeting (if any).
- Appeal to your target audience – who may have changed tastes from when the blog post was originally made.
Remember that your meta tags in particular act like a brief advertisement for your blog post, since this is what the user first sees when your blog post is shown in the search results page.
Take a look at your blog post’s click-through rate on Google Search Console – if it falls below 2%, it’s definitely time for new meta tags.
Replace Outdated Information and Statistics
Updating blog content with current studies and statistics enhances the relevance and credibility of your post. By providing up-to-date information, you help your audience make better, well-informed decisions, while also showing that your content is trustworthy.
Tighten or Expand Ideas
Your old content might be too short to provide real value to users – or you might have rambled on and on in your post. It’s important to evaluate whether you need to make your content more concise, or if you need to elaborate more.
Keep the following tips in mind as you refine your blog post’s ideas:
- Evaluate Helpfulness: Measure how well your content addresses your readers’ pain points. Aim to follow the E-E-A-T model (Experience, Expertise, Authoritativeness, Trustworthiness).
- Identify Missing Context: Consider whether your content needs more detail or clarification. View it from your audience’s perspective and ask if the information is complete, or if more information is needed.
- Interview Experts: Speak with industry experts or thought leaders to get fresh insights. This will help support your writing, and provide unique points that enhance the value of your content.
- Use Better Examples: Examples help simplify complex concepts. Add new examples or improve existing ones to strengthen your points.
- Add New Sections if Needed: If your content lacks depth or misses a key point, add new sections to cover these areas more thoroughly.
- Remove Fluff: Every sentence should contribute to the overall narrative. Eliminate unnecessary content to make your post more concise.
- Revise Listicles: Update listicle items based on SEO recommendations and content quality. Add or remove headings to stay competitive with higher-ranking posts.
Improve Visuals and Other Media
No doubt that there are tons of old graphics and photos in your blog posts that can be improved with the tools we have today. Make sure all of the visuals used in your content are appealing and high quality.
Update Internal and External Links
Are your internal and external links up to date? They need to be for your SEO and user experience. Outdated links can lead to broken pages or irrelevant content, frustrating readers and hurting your site’s performance.
You need to check for any broken links on your old blog posts, and update them ASAP. Updating your old blog posts can also lead to new opportunities to link internally to other blog posts and pages, which may not have been available when the post was originally published.
Optimize for Conversions
When updating content, the ultimate goal is often to increase conversions. However, your conversion goals may have changed over the years.
So here’s what you need to check in your updated blog post. First, does the call-to-action (CTA) still link to the products or services you want to promote? If not, update it to direct readers to the current solution or offer.
Second, consider where you can use different conversion strategies. Don’t just add a CTA at the end of the post.
Last, make sure that the blog post leverages product-led content. It’s going to help you mention your products and services in a way that feels natural, without being too pushy. Being subtle can be a high ROI tactic for updated posts.
Key Takeaway
Reviving old blog articles for SEO is a powerful strategy that can breathe new life into your content and boost your website’s visibility. Instead of solely focusing on creating new posts, taking the time to refresh existing content can yield impressive results, both in terms of traffic and conversions.
By implementing these strategies, you can transform old blog posts into valuable resources that attract new readers and retain existing ones. So, roll up your sleeves, dive into your archives, and start updating your content today—your audience and search rankings will thank you!
SEO
How Compression Can Be Used To Detect Low Quality Pages
The concept of Compressibility as a quality signal is not widely known, but SEOs should be aware of it. Search engines can use web page compressibility to identify duplicate pages, doorway pages with similar content, and pages with repetitive keywords, making it useful knowledge for SEO.
Although the following research paper demonstrates a successful use of on-page features for detecting spam, the deliberate lack of transparency by search engines makes it difficult to say with certainty if search engines are applying this or similar techniques.
What Is Compressibility?
In computing, compressibility refers to how much a file (data) can be reduced in size while retaining essential information, typically to maximize storage space or to allow more data to be transmitted over the Internet.
TL/DR Of Compression
Compression replaces repeated words and phrases with shorter references, reducing the file size by significant margins. Search engines typically compress indexed web pages to maximize storage space, reduce bandwidth, and improve retrieval speed, among other reasons.
This is a simplified explanation of how compression works:
- Identify Patterns:
A compression algorithm scans the text to find repeated words, patterns and phrases - Shorter Codes Take Up Less Space:
The codes and symbols use less storage space then the original words and phrases, which results in a smaller file size. - Shorter References Use Less Bits:
The “code” that essentially symbolizes the replaced words and phrases uses less data than the originals.
A bonus effect of using compression is that it can also be used to identify duplicate pages, doorway pages with similar content, and pages with repetitive keywords.
Research Paper About Detecting Spam
This research paper is significant because it was authored by distinguished computer scientists known for breakthroughs in AI, distributed computing, information retrieval, and other fields.
Marc Najork
One of the co-authors of the research paper is Marc Najork, a prominent research scientist who currently holds the title of Distinguished Research Scientist at Google DeepMind. He’s a co-author of the papers for TW-BERT, has contributed research for increasing the accuracy of using implicit user feedback like clicks, and worked on creating improved AI-based information retrieval (DSI++: Updating Transformer Memory with New Documents), among many other major breakthroughs in information retrieval.
Dennis Fetterly
Another of the co-authors is Dennis Fetterly, currently a software engineer at Google. He is listed as a co-inventor in a patent for a ranking algorithm that uses links, and is known for his research in distributed computing and information retrieval.
Those are just two of the distinguished researchers listed as co-authors of the 2006 Microsoft research paper about identifying spam through on-page content features. Among the several on-page content features the research paper analyzes is compressibility, which they discovered can be used as a classifier for indicating that a web page is spammy.
Detecting Spam Web Pages Through Content Analysis
Although the research paper was authored in 2006, its findings remain relevant to today.
Then, as now, people attempted to rank hundreds or thousands of location-based web pages that were essentially duplicate content aside from city, region, or state names. Then, as now, SEOs often created web pages for search engines by excessively repeating keywords within titles, meta descriptions, headings, internal anchor text, and within the content to improve rankings.
Section 4.6 of the research paper explains:
“Some search engines give higher weight to pages containing the query keywords several times. For example, for a given query term, a page that contains it ten times may be higher ranked than a page that contains it only once. To take advantage of such engines, some spam pages replicate their content several times in an attempt to rank higher.”
The research paper explains that search engines compress web pages and use the compressed version to reference the original web page. They note that excessive amounts of redundant words results in a higher level of compressibility. So they set about testing if there’s a correlation between a high level of compressibility and spam.
They write:
“Our approach in this section to locating redundant content within a page is to compress the page; to save space and disk time, search engines often compress web pages after indexing them, but before adding them to a page cache.
…We measure the redundancy of web pages by the compression ratio, the size of the uncompressed page divided by the size of the compressed page. We used GZIP …to compress pages, a fast and effective compression algorithm.”
High Compressibility Correlates To Spam
The results of the research showed that web pages with at least a compression ratio of 4.0 tended to be low quality web pages, spam. However, the highest rates of compressibility became less consistent because there were fewer data points, making it harder to interpret.
Figure 9: Prevalence of spam relative to compressibility of page.
The researchers concluded:
“70% of all sampled pages with a compression ratio of at least 4.0 were judged to be spam.”
But they also discovered that using the compression ratio by itself still resulted in false positives, where non-spam pages were incorrectly identified as spam:
“The compression ratio heuristic described in Section 4.6 fared best, correctly identifying 660 (27.9%) of the spam pages in our collection, while misidentifying 2, 068 (12.0%) of all judged pages.
Using all of the aforementioned features, the classification accuracy after the ten-fold cross validation process is encouraging:
95.4% of our judged pages were classified correctly, while 4.6% were classified incorrectly.
More specifically, for the spam class 1, 940 out of the 2, 364 pages, were classified correctly. For the non-spam class, 14, 440 out of the 14,804 pages were classified correctly. Consequently, 788 pages were classified incorrectly.”
The next section describes an interesting discovery about how to increase the accuracy of using on-page signals for identifying spam.
Insight Into Quality Rankings
The research paper examined multiple on-page signals, including compressibility. They discovered that each individual signal (classifier) was able to find some spam but that relying on any one signal on its own resulted in flagging non-spam pages for spam, which are commonly referred to as false positive.
The researchers made an important discovery that everyone interested in SEO should know, which is that using multiple classifiers increased the accuracy of detecting spam and decreased the likelihood of false positives. Just as important, the compressibility signal only identifies one kind of spam but not the full range of spam.
The takeaway is that compressibility is a good way to identify one kind of spam but there are other kinds of spam that aren’t caught with this one signal. Other kinds of spam were not caught with the compressibility signal.
This is the part that every SEO and publisher should be aware of:
“In the previous section, we presented a number of heuristics for assaying spam web pages. That is, we measured several characteristics of web pages, and found ranges of those characteristics which correlated with a page being spam. Nevertheless, when used individually, no technique uncovers most of the spam in our data set without flagging many non-spam pages as spam.
For example, considering the compression ratio heuristic described in Section 4.6, one of our most promising methods, the average probability of spam for ratios of 4.2 and higher is 72%. But only about 1.5% of all pages fall in this range. This number is far below the 13.8% of spam pages that we identified in our data set.”
So, even though compressibility was one of the better signals for identifying spam, it still was unable to uncover the full range of spam within the dataset the researchers used to test the signals.
Combining Multiple Signals
The above results indicated that individual signals of low quality are less accurate. So they tested using multiple signals. What they discovered was that combining multiple on-page signals for detecting spam resulted in a better accuracy rate with less pages misclassified as spam.
The researchers explained that they tested the use of multiple signals:
“One way of combining our heuristic methods is to view the spam detection problem as a classification problem. In this case, we want to create a classification model (or classifier) which, given a web page, will use the page’s features jointly in order to (correctly, we hope) classify it in one of two classes: spam and non-spam.”
These are their conclusions about using multiple signals:
“We have studied various aspects of content-based spam on the web using a real-world data set from the MSNSearch crawler. We have presented a number of heuristic methods for detecting content based spam. Some of our spam detection methods are more effective than others, however when used in isolation our methods may not identify all of the spam pages. For this reason, we combined our spam-detection methods to create a highly accurate C4.5 classifier. Our classifier can correctly identify 86.2% of all spam pages, while flagging very few legitimate pages as spam.”
Key Insight:
Misidentifying “very few legitimate pages as spam” was a significant breakthrough. The important insight that everyone involved with SEO should take away from this is that one signal by itself can result in false positives. Using multiple signals increases the accuracy.
What this means is that SEO tests of isolated ranking or quality signals will not yield reliable results that can be trusted for making strategy or business decisions.
Takeaways
We don’t know for certain if compressibility is used at the search engines but it’s an easy to use signal that combined with others could be used to catch simple kinds of spam like thousands of city name doorway pages with similar content. Yet even if the search engines don’t use this signal, it does show how easy it is to catch that kind of search engine manipulation and that it’s something search engines are well able to handle today.
Here are the key points of this article to keep in mind:
- Doorway pages with duplicate content is easy to catch because they compress at a higher ratio than normal web pages.
- Groups of web pages with a compression ratio above 4.0 were predominantly spam.
- Negative quality signals used by themselves to catch spam can lead to false positives.
- In this particular test, they discovered that on-page negative quality signals only catch specific types of spam.
- When used alone, the compressibility signal only catches redundancy-type spam, fails to detect other forms of spam, and leads to false positives.
- Combing quality signals improves spam detection accuracy and reduces false positives.
- Search engines today have a higher accuracy of spam detection with the use of AI like Spam Brain.
Read the research paper, which is linked from the Google Scholar page of Marc Najork:
Detecting spam web pages through content analysis
Featured Image by Shutterstock/pathdoc
SEO
New Google Trends SEO Documentation
Google Search Central published new documentation on Google Trends, explaining how to use it for search marketing. This guide serves as an easy to understand introduction for newcomers and a helpful refresher for experienced search marketers and publishers.
The new guide has six sections:
- About Google Trends
- Tutorial on monitoring trends
- How to do keyword research with the tool
- How to prioritize content with Trends data
- How to use Google Trends for competitor research
- How to use Google Trends for analyzing brand awareness and sentiment
The section about monitoring trends advises there are two kinds of rising trends, general and specific trends, which can be useful for developing content to publish on a site.
Using the Explore tool, you can leave the search box empty and view the current rising trends worldwide or use a drop down menu to focus on trends in a specific country. Users can further filter rising trends by time periods, categories and the type of search. The results show rising trends by topic and by keywords.
To search for specific trends users just need to enter the specific queries and then filter them by country, time, categories and type of search.
The section called Content Calendar describes how to use Google Trends to understand which content topics to prioritize.
Google explains:
“Google Trends can be helpful not only to get ideas on what to write, but also to prioritize when to publish it. To help you better prioritize which topics to focus on, try to find seasonal trends in the data. With that information, you can plan ahead to have high quality content available on your site a little before people are searching for it, so that when they do, your content is ready for them.”
Read the new Google Trends documentation:
Get started with Google Trends
Featured Image by Shutterstock/Luis Molinero